Precautions

If your condition does not improve or if it becomes worse, check with your doctor.

Using this medicine while you are pregnant can harm your unborn baby. Use an effective form of birth control to keep from getting pregnant. Your birth control pills may not work as well while you are using this medicine. If you think you have become pregnant while using this medicine, tell your doctor right away.

Do not take this medicine if you are also using disulfiram (Antabuse®) or methoxyflurane (Penthrane®).

Drinking alcoholic beverages while taking metronidazole may cause stomach pain, nausea, vomiting, headache, or flushing or redness of the face. Other alcohol-containing preparations (e.g., elixirs, cough syrups, tonics) may also cause problems. Do not drink alcoholic beverages or take other products containing propylene glycol while you are taking Helidac® and for at least 3 days after stopping it.

Metronidazole may cause some people to become dizzy, clumsy, or trouble seeing clearly.

Children or teenagers who have or who are recovering from chickenpox or influenza should not use this combination of medicines unless directed by the child's doctor. If nausea or vomiting occurs after taking this combination of medicines, check with the child's doctor.

Tetracycline may cause your skin to be more sensitive to sunlight than it is normally. Exposure to sunlight, even for brief periods of time, may cause a skin rash, itching, redness or other discoloration of the skin, or a severe sunburn. When you begin taking tetracycline:

Stay out of direct sunlight, especially between the hours of 10:00 a.m. and 3:00 p.m., if possible.

Wear protective clothing, including a hat. Also, wear sunglasses.

Apply a sunblock product that has a skin protection factor (SPF) of at least 15. Some patients may require a product with a higher SPF, especially if they have a fair complexion. If you have any questions about this, check with your doctor.

Apply a sunblock lipstick that has an SPF of at least 15 to protect your lips.

Do not use a sunlamp or tanning bed or booth.

You may still be more sensitive to sunlight or sunlamps for 2 weeks to several months or more after stopping tetracycline. If you have a severe reaction, check with your doctor.

Bismuth subsalicylate may cause dark tongue and/or black stools. This is only temporary and will go away after you stop taking this medicine.

This medicine lowers the number of some types of blood cells in your body. Because of this, you may bleed or get infections more easily. Avoid people who are sick. Wash your hands often. Stay away from rough sports or other situations where you could be bruised, cut, or injured. Brush and floss your teeth gently. Be careful when using sharp objects, including razors and fingernail clippers.

If you develop a skin rash, hives, or any allergic reaction to this medicine, stop taking the medicine and check with your doctor as soon as possible.

Before having surgery (including dental surgery) with a general anesthetic, tell the medical doctor or dentist in charge that you are taking tetracycline in this combination of medicines.

Make sure any doctor or dentist who treats you knows that you are using this medicine. This medicine may affect the results of certain medical tests.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.